Severs disease is by far the most common cause of heel pain in young children, the condition commonly occurs in kids around the age of 10-15 years. Severs is a traction apophysitis in which inflammation of the calcaneal apophysis (growth plate) occurs as a result of overuse or micro trauma.
In the following picture the “gap” in the heel bone is the apophysis, this is where growth of the calcaneus/heel bone originates from. When growth is almost complete, around the age of 14, this plate fuses into bone.
As mentioned severs disease is caused by micro trauma and over use, this can include excessive foot pronation (foot rolling in), tight calf muscles, increase in sporting activities and inappropriate footwear. These all put extra sheering forces on the growth plate leading to aggravation and resultant pain.
Signs and symptoms of this include pain on squeezing of the heel, absence of swelling and redness, child describing pain as a dull ache, limping and pain with increased activity.